Java 8 new inheritance model - insert if James Gosling were dead he'd be spinning in his grave jokes here. (Thanks to Russel Winder for tracking all this stuff much more closely that I ever would if I didn't have him to do it for me.)

Harry lending a fleece to a friend - What colour do you want? Full zip? Half zip? Do you not want a zip?

C++ Quiz - the C++ community seems to delight in this kind of thing, while advocates of other languages like to point and laugh which rather misses the point. You could construct questions like this for any useful language.

After a bit (and I mean a little bit) of wandering around it was clear that my nurdle about in the code last weekend hadn't fixed the CycleStreets app sat-nav mode after all. In fact it was just as bad as it was before, even though I'd completely changed the calculations it was doing. I drew diagrams and everything while trying to work it out. Bashed my head against it today and realised my diagrams were right, but my implementation was wrong. Popped in the missing Math.abs call. Let's see if it survives contact with reality tomorrow morning.